As the speed of operation of textile yarn processing machines, such as yarn texturing machines, has increased in recent years, it has become necessary to replenish yarn supply packages more often and this results in an increase in the cost of operating the machines and in the cost of producing textured yarn thereon. The faster withdrawal of yarn from the yarn supply packages has prompted manufacturers to recognize the advantage to be gained by using larger diameter yarn supply packages. In producing larger size yarn supply packages, the yarn producers have increased the diameter of the yarn supply package but have maintained the width or yarn traversing surface substantially the same. The width or yarn traversing surface of the yarn packages have not been increased because the tension and other yarn withdrawal characteristics may be undesirably changed.
In order to provide a continuous supply of feeder yarn, the supply packages have been paired with one package being an active yarn feeding package and the other adjacent package being tailed thereto and acting as a reserve supply of yarn. These adjacent pairs of yarn supply packages have normally been supported with the longitudinal axis of the yarn supply packages in acute angular relationship with each other so that the yarn withdrawal ends face in generally the same direction and toward a yarn guide positioned at the apex of the acute angle formed by the longitudinal axis of each of the yarn packages. With the paired supply packages being supported in this position, an increase in the diameter of the packages has resulted in the need for a greater distance to be provided between the longitudinal axis of each of the paired yarn supply packages, thereby requiring a greatly enlarged increase in the dimensions of the yarn creel.
In many instances, the textile yarn processing machines are positioned in a manufacturing plant with a certain spacing therebetween and it is not possible to increase the size of the adjacent yarn supply creels because of the limited floor space. In some instances, the creels have been increased in height in order to support the larger diameter supply packages. However, increasing the height of the creel also creates problems of positioning unusually heavy, full yarn packages on the creel, particularly at the higher elevations. Also, the vertical extension of the creel creates problems by forming objectionable tortuous yarn paths for movement of the feeder yarn from the yarn supply package to the yarn processing station of the textile machine.
As yarn supply packages of larger diameter have become more popular, such as 50 pound POY yarn packages having a diameter of approximately 14 inches and a yarn width of approximately 10 inches, the standard fixed type of creels have been replaced by rotary creels which conserve space and provide easier replacement of the exhausted yarn supply packages. One example of this type of rotary yarn supply creel is disclosed in German Offenlegungsschrift No. 34 08 808 published Sept. 20, 1984. The creel of this publication has the advantages of being able to rotate the creel to move the yarn package support spindles from their normal position to a convenient position for replacing exhausted yarn supply packages. However, both the paired feeding and reserve yarn supply packages of this publication are supported on the creel in generally the conventional acute angular position relative to each other, as has been used for years in the fixed type of creel. In this arrangement, the feeding yarn supply package and adjacent reserve yarn package are supported with their axes in an acute angular relationship to each other and with the yarn withdrawal ends of the yarn supply packages facing inwardly toward the center of the rotary creel.
When 50 pound yarn supply packages are supported on the creel of this publication, the large diameter of the feeding yarn supply package and adjacent reserve yarn supply package does not permit placing two full yarn supply packages on adjacent supporting spindles. Thus, a full reserve yarn supply package can be placed on its support spindle only after the diameter of the adjacent feeding yarn supply package has been considerably reduced. Also, the construction of the rotary creel of this publication does not lend itself to the automated donning and doffing the yarn supply packages. In order to adapt this type of creel to support even larger diameter yarn supply packages, such as 100 pound POY yarn packages having a diameter of approximately 21 inches and a yarn width of approximately 10 inches, the dimensions of the support creel would have to be greatly increased.